This proposed research will seek to investigate the role of specific lymphoid host cells in the establishment and maintenance of experimental periodontal disease in normal and immunologically compromised rodent hosts. We will explore the shifts in specific cell populations and subpopulations during the establishment and progression of experimental periodontal disease in normal and athymic rats using monoclonal antibodies and flow cytofluorometric techniques. We will also investigate the activation state of these subtypes in developing peridontal disease lesions which should provide information on the sequence of cell activity and the roles of the various cell subtypes. We have proposed to explore the nature of these cell roles with an experimental sequence involving adoptive transfer after the use of specific T cell cloning methodology. Specific subpopulations of cloned antigen specific T lymphocytes will be adoptively transferred into immunologically compromised and normal rodent hosts. Further, studies of antigen-studies of antigen-specific B cells, adoptively transferred into normal and immunologically compromised rodent hosts (congenitally athymic) will evaluate the role of antibody and bone resorptive factors in periodontal disease. The methodology employed will utilize monoclonal antibodies as recognition factors and for separation of selected cell population. Analytical procedures will involve flow cytofluorometry, ELISA assay, blastogenic and plaque forming cell assays. The proposal holds promise to enhance understanding of regulatory cell involvement in periodontal disease. Specific promising procedures to ameliorate periodontal disease will be tested.